Our experiments are designed to further investigate the influence of the pituitary of Woffian lens regeneration by determining how the gland is able to enhance regeneration of a lens in organ culture. The main objectives are to: determine the influence of the pitiutary on DNA synthesis in dorsal iris epithelial cells during the first 10-12 days in culture; determine when the process of regeneration in vitro the pituitary is necessary; test the effects of adding hormones such as prolactin, insulin, thyroxine, growth hormone and cortisol to the culture medium on regenerative activities of iris epithelial cells; and to test the effects of dibutyryl CAMP and theophylline on regenerative activities of iris epithelial cells in organ culture. These experiments will help determine whether the pituitary can be directly involved in stimulation of the metaplastic transformation of iris epithelial cells containing melanin into crystallin-containing lens fiber cells.